Nutrient fats having improved digestibility

ABSTRACT

The invention concerns triglyceride compositions useful as nutrient fats having improved digestibility. The compositions comprise: 
     1-95 wt. % of M 2  L; 
     5-65 wt. % of ML 2 , 
     M=saturated fatty acid C 2  -C 14  ; 
     L=unsaturated fatty acid C 18  +, 
     35-99.5% of the total L being bonded at the 2-position.

This application claims benefit of international applicationPCT/EP94/01041, filed Mar. 31, 1994.

BACKGROUND OF THE INVENTION

Synthetic triglycerides comprising two different groups of fatty acidresidues, i.e. fatty acids consisting of ω-3 unsaturated fatty acids andsaturated fatty acids in the C₈ -C₁₀ range, wherein the fatty acidresidues of the saturated C₈ -C₁₀ range are preferably bonded to the1,3-positions, while the ω-3 fatty acids are preferably derived fromplant oils, marine plankton oils, fungal oils or fish oils are knownfrom U.S. Pat. No. 4,873,768 (although this is contradictory to thedisclosure in column 4, lines 7-10 of U.S. Pat. No. 4,873,768, where itis stated that the saturated C₈ -C₁₀ fatty acid residues are preferablybonded to adjacent carbon atoms). A prerequisite for these triglyceridesis that at least one ω-3 fatty acid residue is present and at least oneC₈ -C₁₀ saturated fatty acid residue. Therefore, the maximum amount ofω-3 fatty acid residues is 66 wt. % (i.e. two of these residues arepresent) from which at least 50% is bonded at the 2-position.

The above-mentioned triglycerides can be used in enterally orparenterally administered compositions. The above-mentioned fats providea means for the addition of fat calories while the fats do not give riseto problems in the the reticulo-endothecial system and do not act assubstrates for prostaglandin systems.

According to U.S. Pat. No. 4,906,664, nutritional supports for patientssuffering from cancer cachexia are obtained when the diet contains anamount of triglycerides containing medium-chain fatty acids andunsaturated ω-3 long-chain fatty acid.

In WO 92/19237, pharmaceutical compositions are disclosed that can beused in enteral preparations for treatment of lipid malabsorption. Thelipids contain MLM-type triglycerides (M=medium-chain fatty acids C₆-C₁₃ and L=long-chain fatty acids C₁₄ -C₂₄, e.g. unsaturated fatty acidresidues). It is disclosed that the lipid absorption is greater for MLMthan for randomized MLM triglycerides.

According to WO 91/095597, triglycerides that contain at least one C₂-C₅ fatty acid residue and at least one C₁₆ -C₂₄ fatty acid residue canbe used as a biological agent with effect on the intestinal mucosa.

From the above-mentioned references it can therefore be concluded thatfat absorption, and therefore the digestibility of a fat, is improvedwhen the 1,3-positions in the fat are taken by medium-chain fatty acids.So, if a graph were to be drawn, demonstrating the digestibility againstthe content of medium-chain fatty acids in the 1,3-positions, it wouldbe found that the digestibility of MLM fat (=M=medium-chain fatty acid)would be far better than that of LLL fats. Simultaneously, digestibilitywould be expected to be in linear relationship to the percentage ofmedium-chain fatty acids present in the 1,3-positions of triglycerides.Surprisingly, however, it was found that the digestibility of fatscomprising a mixture of M₂ L and L₂ M fats with an overall M content inthe 1,3-position varying between 0 and 100% has a digestibility which isgreater than expected in theory.

SUMMARY OF THE INVENTION

Therefore, we found triglyceride compositions having a digestibilitythat is higher than should be expected. These triglyceride compositionscomprise fats derived from saturated medium/short-chain fatty acids andfats derived from long-chain unsaturated fatty acids, wherein thecomposition comprises:

1-95 wt. % of M₂ L-type triglycerides and

5-65 wt. % of L₂ M-type triglycerides,

M being saturated fatty acid residues with 2-14 carbon atoms, preferably6-14 carbon atoms;

L being mono- or poly-unsaturated fatty acid residues with at least 18carbon atoms, the fatty acid distribution of L being such that 35-99.5%,preferably 40-80%, of the total L present being bonded at the2-position.

DETAILED DESCRIPTION OF THE INVENTION

Although the above-mentioned triglycerides are all very useful, apreference is expressed for the use of fats wherein the total amount ofL is not 33-67 wt. % in case L is C₁₈₊ω-3 only.

In particular, a preference is expressed for the application of atriglyceride composition according to the invention, wherein the amountof M₂ L=10-50 wt. % and the amount of L₂ M=30-60 wt. %.

Although M can range from 2-14 C-atoms, a preference is expressed forthe use of saturated fatty acid residues having 8-12 C atoms.

As unsaturated fatty acid residue L, a great number of differentunsaturated fatty acids can be applied. Examples thereof are oleic,linolenic, linolenic (both α and γ) and the essential fatty acids havingat least 20 C-atoms, such, as DHA (=C_(22:6)ω3), E.P.A. (=C_(20:5)ω3),or arachidonic acid (=C_(20:4)ω6).

Although the above-mentioned triglycerides could be used per se, apreference is expressed for the application of blends of theabove-mentioned fats with other fats. In these blends the presence ispreferred of a structuring fat which makes it easier to apply the fatsin food products.

Therefore, in another embodiment of the invention, We found blends oftriglycerides comprising at least a fat A and a structuring fat B,wherein

fat A is a fat according to the invention which is present in 0.3-70 wt.%, preferably 5-45 wt % fat B is a fat containing saturated fatty acidresidues with 12-24 carbon atoms, its SAFA content being 20-80 wt. %,which fat B is present in amounts of 30-99.7 wt. %, preferably 55-95 wt%

The structuring properties of fat B are best when fat B displays a solidfat content at 20° C. (NMR pulse) of more than 15, preferably more than20.

Suitable fats B are obtained by blending fats C and D, wherein fat C hasan (L₂ S+L₃) level of more than 35 wt. %, preferably 35-85 wt % and fatD displays an N₂₀ >30, L being as defined above, S being saturated fattyacid residues with 16-22 C atoms.

The preferred fats B which display the best structuring properties arefats B, wherein more than 25 wt %, preferably 25-60 wt % of LS₂ ispresent (L and S as defined above).

Other suitable fats B have an (H₂ M'+M'H₂) content of more than 60 wt.%, H being saturated fatty acid residue with ≧16 C-atoms, preferably16-18 C-atoms, M' being saturated fatty acid residue with 8-14 C-atoms,preferably 12-14 C-atoms.

The blends very suitably should display SAFA levels of 20-40 wt. %, MUFAlevels of 10-70 wt. % and PUFA levels of 10-70 wt. %, whilesimultaneously the ratio between ω-6 and ω-3 unsaturated fatty acidsshould vary from 2-20, preferably from 4-15.

The fats and fat blends according to the invention can be applied as afat phase in food products, such as spreads, margarines, creamalternatives, chocolate, confectionery, bakery products, sauces, icecreams, table oils, dressings, mayonnaises, enteral or parenteralproducts, wherein the fat phase at least partly comprises a fataccording to the invention. The fats are also very useful in infantformulas, in which case the compositions also comprise proteins andcarbohydrates (cf. EP 496,456).

The amount of fat in these products can vary between wide ranges,suitable amounts being 1-80 wt. %; however, the actual amount willdepend largely on the food product.

The fats according to our invention can be made by applying enzymicconversions, e.g. as disclosed in GB 1,577,933. The starting materialshave to be selected carefully. Sources for the medium-chain fatty acidsare, e.g., palm kernel oils or coconut oils. Sources for the unsaturatedlong-chain fatty acids are, e.g., sunflower oil, high-oleic sunfloweroil, soybean oil, rapeseed oil, borage, evening primrose oil, fish oil,safflower oil, linseed or oils derived from algal or fungal sources,such as Mortierella species.

EXAMPLES

1. Preparation of an MLM-rich fat

1.1 Glycerol (1.25 g) was reacted with decanoic anhydride (8.86 g) inthe presence of dichloromethane (63 ml) and Rhizomucor miehei lipase(2.5 g supported lipase). The reaction was performed for 10 hrs at 20°C. The product mixture was filtered and cooled over dry-ice. Theprecipitate (1.3-dicaprin) was collected and treated with silica toyield 2.76 g purified diglyceride.

1.2 The diglyceride was reacted with 3.75 g linoleic anhydride in thepresence of 60 ml dichloromethane and 4-N,N-dimethylaminopyridine (0.255g). After 2 hrs at 20° C., the mixture was cooled over dry-ice and theproduct collected by filtration (yield 7.6 g). After purification overalumina 4.8 g of a pure product was obtained. From analysis we couldconclude that this product contained 99% M₂ L, comprising 66.8 wt %C_(10:0) and 33.2 wt % C_(18:2), while 84.6% of the 1,3-positions wereoccupied by C_(10:0) (on mole basis).

2. Digestibility

The digestibility of the above MLM-fat was measured as follows:

1 g of fat was added to 100 ml of an aqueous solution containing 0.261 gsodium taurodeoxycholate, 0.368 g calcium chloride and 0.877 g sodiumchloride. An emulsion was formed by homogenisation and ultrasonication,and pH adjusted to 7.0. Hydrolysis of the emulsion was determined byaddition of 20-40 μl of 1% solution of crude pancreatic lipase (SigmaType II, buffered to 0 ml of the emulsion at 37°-40° C. Fatty acidreleased by the lipase was neutralised by addition of sodium hydroxideto maintain a pH of 7.0. Rate of hydrolysis was calculated from the rateof reagent added. Mean slope was determined by linear regression in thetime interval from 2 to 10 minutes after addition of enzyme. We found adigestibility of 107.

3. The digestibility of sunflower oil SF-1 was measured by the sameprocedure (63% C_(18:2) ; 24% C_(18:1) ; % M in 1.3:0%). We found adigestibility of 100.

4. For comparison sunflower oil (SF-1) was reacted with C_(10:0) fattyacid in the presence of Rhizomucor miehei lipase. At the end of thereaction the fatty acids and partial glycerides were removed, and theproduct (SF-2) characterised:

    ______________________________________                                                    FAME  2-position                                                  ______________________________________                                        C.sub.8:0     0.6     0.1                                                     C.sub.10:0    27.3    0.9                                                     C.sub.12:0    0.2     --                                                      C.sub.14:0    --      --                                                      C.sub.16:0    3.4     0.8                                                     C.sub.18:0    3.2     3.1                                                     C.sub.18:1    17.9    25.1                                                    C.sub.18:2    46.5    68.3                                                    C.sub.20      0.3     0.6                                                     C.sub.22      0.6     0.1                                                     C.sub.24      0.2                                                             ______________________________________                                    

48% of the total `L` (C_(18:1) +C_(18:2)) was esterified to the sn-2position. The sn-1,3 positions comprised -54% C_(8:0) +C_(10:0) on amole basis.

The M₂ L content and ML₂ content of SF-2 was 41.0% and 38.9%respectively. The digestibility of the two oils was measured asdescribed above with the following result:

    ______________________________________                                                   Relative lipolysis rate (mean ± SEM)                            ______________________________________                                        SF-1         100 ± 1.8                                                                              (n = 8)                                              SF-2         113.4 ± 2.7                                                                            (n = 8)                                              ______________________________________                                    

The SF-2 oil was hydrolysed in vitro at a significantly faster ratecompared to the SF-1 oil.

5. From the above, it can be concluded that the digestibility of SF-1was 100 (so for 0% M in 1,3); for SF-2 we found 113.4 (for 54% C₁₀ +C₈in 1,3) and for MLM (with 84.6% M in 1,3) we found 107. So, the SF-2showed a digestibility that is greater than could be expected on basisof a linear relationship between % M in 1,3 and the digestibility.

We claim:
 1. Triglyceride composition comprising fats derived fromsaturated medium/short-chain fatty acids and fats derived fromlong-chain unsaturated fatty acids, wherein the compositioncomprises:1-95 wt. % of M₂ L-type triglycerides and 5-65 wt. % of L₂M-type triglycerides,M being saturated fatty acid residues with 2-14carbon atoms, L being mono- or poly-unsaturated fatty acid residues withat least 18 carbon atoms, the fatty acid distribution of L being suchthat 35-99.5%, of the total L present being bonded at the 2-position. 2.Triglyceride composition according to claim 1, wherein the amount of M₂L=10-50 wt. % and the amount of L₂ M=30-60 wt. %.
 3. Triglyceridecomposition according to claim 1, whereinM is saturated C₈ -C₁₂ fattyacid residue and L is mono- or poly-unsaturated C₁₈ fatty acid residuefrom oleic acid, linoleic acid or linolenic acid.
 4. Triglyceridecomposition according to claim 1, wherein L is an essential fatty acidwith at least 20 carbon atoms.
 5. Triglyceride composition according toclaim 4 wherein is DHA (C_(22:)ω3) or E.P.A. (C_(20:5)ω3).
 6. Blend oftriglycerides comprising at least a fat A and a structuring fat B,whereinfat A is a fat according to claim 1 and is present in 0.3-70 wt.%; fat B is a fat containing saturated fatty acid residues with 12-24carbon atoms, its SAFA content being 20-80 wt. %, which fat B is presentin amounts of 30-99.7 wt. %.
 7. Blend according to claim 6, wherein fatB displays a solid fat content at 20° C. (NMR pulse) of more than
 20. 8.Blend according to claim 6, wherein fat B displays a solid fat contentat 20° C. (NMR pulse) of more than
 15. 9. Blend according to claim 6,wherein fat B is obtained by blending fats C and D, wherein fat C has an(L₂ S+L₃) level of more than 35 wt. % and fat D displays an N₂₀ >30, Lbeing as defined in claim 1, S being saturated fatty acid residues with16-22 C atoms.
 10. Blend according to claim 9, wherein fat B has an LS₂content of more than 25 wt. %.
 11. Blend according to claim 6, whereinfat B has an (H₂ M'+M'₂ H) content of more than 60 wt %, H beingsaturated fatty aid residue with ≧16 C-atoms, M' being saturated fattyacid residue with 8-14 C-atoms and wherein L is oleic, linolenic, DHA(C_(22:)ω3), E.P.A. (C_(20:5)ω3) or arachidonic acid (C_(20:4W6)). 12.Blend according to claim 11 wherein H is a saturated fatty acid residuewith 16-18 C-atoms and M' is a saturated fatty acid residue with 12-14C-atoms.
 13. Food products comprising at least a fat phase, such asspreads, margarines, cream alternatives, chocolate, confectionery,bakery products, sauces, ice creams, table oils, dressings, mayonnaises,enteral or parenteral products wherein the fat phase at least partlycomprises a fat according to claim
 1. 14. Triglyceride compositionaccording to claim 1 wherein M is a saturated fatty acid residue with6-14 carbon atoms and the fatty acid distribution of L is 40-80%.